field which the philosopher regards as his own; and also by pointing
out that, even within this field, there is a growing tendency on the
part of certain sciences to separate themselves from philosophy and
become independent. Thus the psychologist and the logician are
sometimes very anxious to have it understood that they belong among the
scientists and not among the philosophers.

Now, this answer to the question that we have raised undoubtedly
contains some truth. As we have seen from the sketch contained in the
preceding pages, the word philosophy was once a synonym for the whole
sum of the sciences or what stood for such; gradually the several
sciences have become independent and the field of the philosopher has
been circumscribed. We must admit, moreover, that there is to be found
in a number of the special sciences a body of accepted facts which is
without its analogue in philosophy. In much of his work the
philosopher certainly seems to be walking upon more uncertain ground
than his neighbors; and if he is unaware of that fact, it must be
either because he has not a very nice sense of what constitutes
scientific evidence, or because he is carried away by his enthusiasm
for some particular form of doctrine.

Nevertheless, it is just to maintain that the answer we are discussing
is not a satisfactory one. For one thing, we find in it no indication
of the reason why the particular group of disciplines with which the
philosopher occupies himself has been left to him, when so many
sciences have announced their independence. Why have not these, also,
separated off and set up for themselves? Is it more difficult to work
in these fields than in others? and, if so, what reason can be assigned
for the fact?